I've also answered your other thread about using Live Writer, which I don't believe is possible; I just tried to set it up again, and it still doesn't work. Live Writer is built for blogs.

EDIT: SharePoint is a Web-based application, so that's the editor: the browser. You can enhance SharePoint to work better by writing your own coe or using third party tools, but you're still working in the browser.

If you have specific requirements (other than "We are not so happy with the built in HTML one (because of image support)"), I'm sure that there are ways to make SharePoint work better for the specific requirement.

Which editor would you suggest is the question ;-) I think Wikis are meant to be edited over the web, so no specific editor... But it would be nice to have a proper editor
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Peter GfaderMay 14 '11 at 10:21

If I understand the question, you are looking for a client-side editor, rather than using the editor in-browser. I don't think there is one - you are stuck with either the in-browser editor that comes out-of-the-box or a third party one such as Telerik. The Telerik editor used to be widely used in the 2007 version of SharePoint, but in 2010 the built-in one is good enough for most people.

I suppose the client editor for SharePoint is SharePoint Designer but that is for editing page layouts and master pages, not content in web parts or Wiki controls.

Telerik might be beneficial, it does have better image uploading/managing than the Sharepoint editor, we still use it in our 2007 farm because of the need for cross browser support for rich text fields.
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PirateEric♦May 14 '11 at 12:10

Agreed. In SP2010 it is a nice-to-have. In SP2007 Telerik's RADeditor (or an equivalent from another supplier) was pretty much essential.
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SPDoctor♦May 14 '11 at 15:30

Actually Teleriks RADEditor if deployed to a wiki page in 2010 clashes with the SharePoint CE so you only end up with limited functionality from either and a broken wiki editing environment. Do not use the RAD Editor for Wiki page editing.
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pigeonJun 21 '13 at 10:33